1. Field of the Invention
This invention is in the fields of treatment for cardiac disease, treatment of ulcers, gene therapy and molecular imaging.
2. Background of the Invention
Coronary artery disease is the leading cause of morbidity and mortality in the Western world.1 Conventional treatment for coronary artery disease consists of medical therapy as the first-line strategy followed by percutaneous coronary intervention or coronary artery bypass graft. However, a significant number of patients will still have refractory angina despite these treatments.2 For such patients, the alternative approach of delivering potent angiogenic factors to stimulate new vessel growth has undergone intense investigation over the past decade.
Current methods of gene therapy approaches for treatment of cardiovascular disease rely on single therapeutic genes such as vascular endothelial growth factor (VEGF) or fibroblast growth factor (FGF). With the use of various gene transfer techniques, it is now possible to modify cardiac cells to overexpress beneficial proteins or inhibit pathological proteins and achieve desired therapeutic effects.3 The field has expanded tremendously from preclinical studies in the early 1990s to large randomized clinical trials in the early 2000s. Although initial Phase 1 trials in patients with myocardial ischemia provided encouraging results, recent Phase 2 randomized trials (AGENT, VIVA, KAT) yielded only modest benefits.4-6 These inconsistencies have been attributed to the unclear role of single therapeutic genes such as vascular endothelial growth factor or fibroblast growth factor as well as the inability to monitor gene transfer in vivo.7 
During hypoxia, upregulation of hypoxia inducible factor-1 α (HIF-1α) transcriptional factor can activate several downstream angiogenic genes. However, HIF-1α is naturally degraded by prolyl 4-hydroxylase-2 (HIF-PHD2) protein.
The prolyl 4-hydroxylases (PH4s) catalyze the formation of 4-hydroxyproline by the hydroxylation of proline residues in peptide linkages. The P4Hs hydroxylating the hypoxia-inducible factor are cytoplasmic and nuclear enzymes that play a key role in the response of calls to hypoxia.27 Three prolyl hydroxylase isoforms have been identified and use O2 and 2-oxyglutarate as substrates to generate 4-hydroxyproline at residue 402 and/or 564 of HIF-1α14 
The Homo Sapien (human) protein and nucleotide sequences of HIF-PHD2 has been determined and is publicly available through many on-line databases, such as, for example, NCBI (available at www.ncbi.nlm.nih.gov).
There are three human transcript variants for HIF-PHD2. The accession number for transcript variant 1 is (NM—177939). The amino sequence is set forth in SEQ ID NO: 1 and the nucleotide sequence is set forth in SEQ ID NO: 2. The accession number for transcript variant 2 is (NM001017962). The amino acid sequence is set forth in SEQ ID NO: 3 and the nucleotide sequence is set forth in SEQ ID NO: 4. The accession number for transcript variant 3 is (NM004199). The amino acid sequence is set forth in SEQ ID NO: 5 and the nucleotide sequence is set forth in SEQ ID NO: 6.
The rat HIF-PHD2 protein sequence and nucleotide sequence are found at accession number NM001108275. The amino acid sequence is set forth in SEQ ID NO: 7 and the nucleotide sequence is set forth in SEQ ID NO: 8.
The accession number for asparaginyl hydroxylase (“ASPHD” or “ASPH”) is NM—023066. The amino acid sequence is set forth in SEQ ID NO: 12 and the nucleotide sequence is set forth in SEQ ID NO: 13.30 
Newer approaches based on the upstream transcriptional factor HIF-1α may be a more natural choice. HIF-1α is known to control the expression of over 60 genes that affect cell survival and metabolism in adverse conditions, including vascular endothelial growth factor, fibroblast growth factor, insulin-like growth factor, erythropoietin, and nitric oxide synthase among others.3 Unfortunately, HIF-1α has a biological half-life of only approximately 5 minutes under normoxic condition.8 This is because during normoxic condition, HIF-1α is hydroxylated by oxygen-dependent prolyl 4-hydroxylase-2 (PHD2), ubiquitinated, and subsequently degraded.
Thus, a need still exists for a method of treating a vascular disease or disorder in a mammal. In particular, there exists a need to treat cardiovascular diseases, in particular ischemic heart disease and peripheral vascular disease by gene therapy. A need also exists for treatment of decubitis ulcers. A means of monitoring the gene transfer and expression in vivo of the vectors used in the treatment of cardiac diseases, such as for example, ischemic heart disease and peripheral vascular disease, is needed as is a means for monitoring treatment of decubitis ulcers. Further, a need remains for vectors capable of expressing therapeutic agents, such as shRNA molecules, for extended periods of time.